ASTM E1737-96

Test Method for J-Integral Characterization of Fracture Toughness (Withdrawn 1998)

SCOPE
1.1 This test method covers the determination of fracture toughness as characterized by the -integral. Three toughness properties are identified which vary with the amount of crack extension present at test termination:( ) instability without significant prior crack extension (  ); ( ) onset of stable crack extension ( JI   ); ( ) stable crack growth resistance curve ( J-R ).  A fourth quantity (   ) not currently interpretable as a toughness property may be measured at fracture instability following stable crack extension. The method applies specifically to geometries that contain notches and flaws that are sharpened with fatigue cracks. The recommended specimens are generally bend-type specimens that contain deep initial cracks. The loading rate is slow and environmentally assisted cracking is assumed to be negligible.  
1.1.1 The recommended specimens are the pin-loaded compact (C(T)), the single, edge bend (SE(B)), and the pin- loaded disk-shaped compact (DC(T)) specimen. All specimens have in-plane dimensions of constant proportionality for all sizes.  
1.1.2 Specimen dimensions are functions of the ratio of -integral to the material effective yield strength, thus the specimen design details must be based on known or estimates mechanical properties.  
1.1.3 The objective of this test method is to set forth a method and to specify limitations for testing prescribed bend-type specimens that will result in -integral fracture toughness values of materials that will be geometry insensitive.  
1.1.4 The single specimen elastic compliance method is detailed herein, but other techniques for measuring crack length are permissible if they equal or exceed the accuracy requirements of this test method. For example, a dc electric potential method is described in Annex A5.  
1.1.5 A multiple specimen technique for JI   measurement requiring five or more identically prepared specimens tested to different crack extensions and displacements is presented in Annex A4.  
1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Withdrawn
• Publication Date: 31-Dec-1995
• ICS: 19.060 - Mechanical testing
• Technical Committee: E08 - Fatigue and Fracture

Standards Content (Sample)

ASTM EL737 96 1111 0759530 0588820 837
Designation: E 1737 - 96
4ib
Standard Test Method for
J-Integral Characterization of Fracture Toughness'
This standard is issued under the fixed designation E 1737; the number immediately following the designation indicates the year of
originai adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsiion (E) indicates an editorial change since the last revision or reapproval.
1. Scope priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
This test method covers the determination of fracture
1.1
toughness as characterized by the J-integral. Three toughness
2. Referenced Documents
properties are identified which vary with the amount of crack
extension present at test termination: (a) instability without
2.1 ASTM Standards:
significant prior crack extension (Jc): (b) onset of stable crack E 4 Practices for Load Verification of Testing Machines3
extension (JI,>; (c) stable crack growth resistance curve E 399 Test Method for Plane-Strain Fracture Toughness
(J-R).2 A fourth quantity (J,) not currently interpretable as a of Metallic Materials3
E 6 16 Terminology Relating to Fracture Testing3
toughness property may be measured at fracture instability
following stable crack extension. The method applies specif-
3. Terminology
ically to geometries that contain notches and flaws that are
sharpened with fatigue cracks. The recommended specimens
3.1 Terminology E 6 16 is applicable to this test method.
are generally bend-type specimens that contain deep initial
3.2 Definitions:
cracks. The loading rate is slow and environmentally assisted 3.2.1 efective thickness B,[L]-for compliance-based
cracking is assumed to be negligible. crack extension measurements Be = B - (B - BN)2/B.
1.1.1 The recommended specimens are the pin-loaded 3.2.2 efective yield strength, ~,[FL-~l-an assumed
compact (C(T)), the single, edge bend (SE(B)), and the pin- value of uniaxial yield strength that represents the influence
of plastic yielding upon fracture test parameters.
loaded disk-shaped compact (DC(T)) specimen. AU speci-
mens have in-plane dimensions of constant proportionality
NOTE 1-u is calculated as the average of the 0.2 % offset yield
for all sizes.
strength uys, and the ultimate tensiie strength urS, for example:
1.1.2 Specimen dimensions are functions of the ratio of
+
Uy =
J-integral to the material effective yield strength, thus the
2
specimen design details must be based on known or esti-
NOTE 2-In estimating ur, the influence of testing conditions, such
mates mechanical properties.
as loading rate and temperature, should be considered.
1.1.3 The objective of this test method is to set forth a
method and to specis. limitations for testing prescribed 3.2.3 estimated crack extension, Aa [LI-an increase in
bend-type specimens that will result in J-integral fracture estimated crack size (Aa = a - a%).
toughness values of materials that will be geometry insensi- 3.2.4 estimated crack size a[L]-the distance from a
tive. reference plane to the observed crack front developed from
1.
1.1.4 The single specimen elastic compliance method is measurements of elastic compliance or other methods. The
reference plane depends on the specimen form, and it is
detailed herein, but other techniques for measuring crack
normally taken to be either the boundary, or a plane
length are permissible if they equal or exceed the accuracy
containing either the load line or the centerline of a specimen
requirements of this test method. For example, a dc electric
or plate. The reference plane is defined prior to specimen
potential method is described in Annex A5.
deformation.
1.1.5 A multiple specimen technique for JI, measurement
3.2.5 J, J[FL-']-a value of J (the crack extension
requiring five or more identically prepared specimens tested
resistance under conditions of crack-tip plane strain) at
to different crack extensions and displacements is presented
fracture instability prior to the onset of significant stable
in Annex A4.
crack extension.
1.2 The values stated in SI units are to be regarded as the
3.2.6 JI, J[FL-']-a value of J (the crack extension
standard. The values given in parentheses are for informa-
resistance under conditions of crack tip plane strain) near the
only.
tion
onset of stable crack extension as specified in this test
1.3 This standard does not purport to address all of the
method.
safety concerns, anv, associated with its use. It is the
3.2.7 Ju, J[FL-']-a value of J measured at fracture
responsibility of the user of this standard to establish appro-
instability after the onset of significant stable crack exten-
sion. It may be size dependent and a function of test
' This test method is under the jurisdiction of ASTM Committee E-8 on
specimen geometry.
Fatigue and Fr
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